Reduction in IL-33 plasma levels might be involved in T cell dysregulation in chronic lymphocytic leukemia

Serum interleukin-33 and soluble suppression of tumorigenicity 2 in pediatric leukemia with febrile neutropenia

The purpose of this study was to evaluate the association between interleukin-33 (IL-33) and its receptor Soluble Suppression of Tumorigenicity-2 (sST2) levels and bacterial infections during febrile neutropenia (FN) in pediatric patients with acute lymphoblastic leukemia (ALL). In this prospective, case-control study, participants were divided into 3 groups: ALL patients with FN (Group A), ALL patients without neutropenia and fever (Group B), and healthy children without infection and chronic disease (Group C). There were 30 cases in each group. Blood samples for IL-33 and sST2 have been drawn from patients in Group A before the initiation of treatment and on days 1 and 5 of treatment, and from patients in Groups B and C at initiation. At admission, mean IL-33 level (39.02 ± 26.40 ng/L) in Group B and mean sST2 level (185.3 ± 371.49 ng/ml) in Group A were significantly higher than the other groups (p = 0.038, p < 0.001, respectively). No difference was observed in the mean IL-33 and sST2 levels in the 5-day follow-up of patients in Group A (p = 0.82, p = 0.86, respectively). IL-33 and sST2 levels were not associated with fever duration, neutropenia duration or length of hospitalization. While C-reactive protein (CRP) was significantly higher in patients with positive blood culture (p = 0.021), IL-33 (p = 0.49) and sST2 (p = 0.21) levels were not associated with culture positivity.  Conclusion: IL-33 and sST2 levels were not found valuable as diagnostic and prognostic markers to predict bacterial sepsis in patients with FN. What is Known: • Neutropenic patients are at high risk of serious bacterial and viral infections, but the admission symptom is often only fever. • Febrile neutropenia has a high mortality rate if not treated effectively. What is New: • Febrile neutropenia is not only caused by bacterial infections. Therefore, new biomarkers should be identified to prevent overuse of antibiotics. • Specific biomarkers are needed to diagnose bacterial sepsis in the early phase of febrile neutropenia.

The association of serum IL-33/ST2 expression with hepatocellular carcinoma

BACKGROUND

IL-33 is a multifunctional cytokine with dual functions. However, the clinicopathological and prognostic significance of IL-33 in cancer patients, especially in patients with hepatocellular carcinoma (HCC), remains controversial. Therefore, we conducted a study of 565 patients with HCC and 561 healthy controls and performed a meta-analysis to quantitatively evaluate the above problems.

METHODS

We collected blood from 565 patients with HCC and 561 healthy controls. ELISA was used to detect the concentrations of IL-33 and ST2 in the serum, and RT‒PCR was used to detect the levels of IL-33 and ST2 mRNA. Meanwhile, we collected comprehensive literature on IL-33 and the clinical characteristics of cancer patients retrieved from the PubMed, Web of Science and CNKI databases as of December 2022. An odds ratio (OR) with a 95% confidence interval (CI) was used to estimate the impact through overall and stratified analyses.

RESULTS

Compared with the healthy control group, the levels of ST2 mRNA and serum in the peripheral blood of HCC patients increased (p < 0.05), while the levels of IL-33 mRNA and serum showed no significant difference between the two groups (p > 0.05). In the meta-analysis section, at the tissue level, the overall analysis showed that the expression of IL-33 was positively correlated with tumor stage, histological grade, distant metastasis, and tumor size. Compared with patients with low IL-33 expression, the 3-year overall survival (OS) rate (OR = 3.467, p < 0.001) and 5-year OS rate (OR = 2.784, p < 0.001) of patients with high IL-33 expression were lower. At the serum expression level, the overall analysis showed that the expression of IL-33 increased the risk of cancer, and the serum level of IL-33 was positively correlated with tumor stage and vascular invasion.

CONCLUSION

IL-33/ST2 is a useful predictive or prognostic biomarker in clinical evaluation and may be used as a potential therapeutic target, but much research is needed to verify this hypothesis.

Plasma IL-33 levels are decreased in patients with high-risk myelodysplastic syndrome and show no correlation with pro-inflammatory IL-6 levels

Aberrant inflammatory signaling has been shown to be a key pathogenic driver in myelodysplastic syndromes (MDS). Abnormal IL-33 expression has been implicated in inflammatory, immune-related disorders and, some tumors. However, its role in MDS remains widely unknown. This study aimed to evaluate the relationship between plasma levels of IL-33, clinical and prognostic data and, IL-6 levels in 101 patients with MDS. A comparative group of 59 healthy individuals was also evaluated. Plasma levels of cytokines were determined by enzyme-linked immunosorbent assay. Lower levels of IL-33 were found in patients with MDS when compared to the control group (p = 0.001), mainly in patients with more advanced stages of the disease and worse prognosis. No significant correlation between the levels of IL-33 and IL-6 was observed (r = 0.175; p = 0.081). These results reinforce the close association between immunological disorders and the pathogenesis of MDS. A greater understanding of the role of inflammatory cytokines in the disease can potentially provide new diagnosis and prognosis markers and new therapeutic targets.

Clinico-Biological Implications of Modified Levels of Cytokines in Chronic Lymphocytic Leukemia: A Possible Therapeutic Role

B-cell chronic lymphocytic leukemia (B-CLL) is the main cause of mortality among hematologic diseases in Western nations. B-CLL is correlated with an intense alteration of the immune system. The altered functions of innate immune elements and adaptive immune factors are interconnected in B-CLL and are decisive for its onset, evolution, and therapeutic response. Modifications in the cytokine balance could support the growth of the leukemic clone via a modulation of cellular proliferation and apoptosis, as some cytokines have been reported to be able to affect the life of B-CLL cells in vivo. In this review, we will examine the role played by cytokines in the cellular dynamics of B-CLL patients, interpret the contradictions sometimes present in the literature regarding their action, and evaluate the possibility of manipulating their production in order to intervene in the natural history of the disease.

The ST2/Interleukin-33 Axis in Hematologic Malignancies: The IL-33 Paradox

Interleukin (IL)-33 is a chromatin-related nuclear interleukin that is a component of IL-1 family. IL-33 production augments the course of inflammation after cell damage or death. It is discharged into the extracellular space. IL-33 is regarded as an “alarmin” able to stimulate several effectors of the immune system, regulating numerous immune responses comprising cancer immune reactions. IL-33 has been demonstrated to influence tumorigenesis. However, as far as this cytokine is concerned, we are faced with what has sometimes been defined as the IL-33 paradox. Several studies have demonstrated a relevant role of IL-33 to numerous malignancies, where it may have pro- and—less frequently—antitumorigenic actions. In the field of hematological malignancies, the role of IL-33 seems even more complex. Although we can affirm the existence of a negative role of IL-33 in Chronic myelogenos leukemia (CML) and in lymphoproliferative diseases and a positive role in pathologies such as Acute myeloid leukemia (AML), the action of IL-33 seems to be multiple and sometimes contradictory within the same pathology. In the future, we will have to learn to govern the negative aspects of activating the IL-33/ST2 axis and exploit the positive ones.

Lymphocyte Subsets and Inflammatory Cytokines of Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma

Almost all multiple myeloma (MM) cases have been demonstrated to be linked to earlier monoclonal gammopathy of undetermined significance (MGUS). Nevertheless, there are no identified characteristics in the diagnosis of MGUS that have been helpful in differentiating subjects whose cancer may progress to a malignant situation. Regarding malignancy, the role of lymphocyte subsets and cytokines at the beginning of neoplastic diseases is now incontestable. In this review, we have concentrated our attention on the equilibrium between the diverse lymphocyte subsets and the cytokine system and summarized the current state of knowledge, providing an overview of the condition of the entire system in MGUS and MM. In an age where the therapy of neoplastic monoclonal gammopathies largely relies on drugs capable of acting on the immune system (immunomodulants, immunological checkpoint inhibitors, CAR-T), detailed knowledge of the the differences existing in benign and neoplastic forms of gammopathy is the main foundation for the adequate and optimal use of new drugs.

The Role of IL-33/ST2 Pathway in Tumorigenesis

Cancer is initiated by mutations in critical regulatory genes; however, its progression to malignancy is aided by non-neoplastic cells and molecules that create a permissive environment known as the tumor stroma or microenvironment (TME). Interleukin 33 (IL-33) is a dual function cytokine that also acts as a nuclear factor. IL-33 typically resides in the nucleus of the cells where it is expressed. However, upon tissue damage, necrosis, or injury, it is quickly released into extracellular space where it binds to its cognate receptor suppression of tumorigenicity 2 (ST2)L found on the membrane of target cells to potently activate a T Helper 2 (Th2) immune response, thus, it is classified as an alarmin. While its role in immunity and immune-related disorders has been extensively studied, its role in tumorigenesis is only beginning to be elucidated and has revealed opposing roles in tumor development. The IL-33/ST2 axis is emerging as a potent modulator of the TME. By recruiting a cohort of immune cells, it can remodel the TME to promote malignancy or impose tumor regression. Here, we review its multiple functions in various cancers to better understand its potential as a therapeutic target to block tumor progression or as adjuvant therapy to enhance the efficacy of anticancer immunotherapies.

IL-33 in Tumor Immunity: Nothing to Sneeze At

Although immunotherapy has been at the forefront of cancer therapy for the last several years, better clinical responses are still desired. Interleukin-33 is perhaps one of the most overlooked antitumor cytokines. Its ability to promote type 1 immune responses, which control tumor growth in preclinical animal models is overshadowed by its association with type 2 immunity and poor prognosis in some human cancers. Accumulating evidence shows that IL-33 is a powerful new tool for restoring and enhancing the body's natural antitumor immunity cycle. Furthermore, the antitumor mechanisms of IL-33 are two-fold, as it can directly boost CD8+ T cell function and restore dendritic cell dysfunction in vivo. Mechanistic studies have identified a novel pathway induced by IL-33 and its receptor ST2 in which dendritic cells avoid dysfunction and retain cross-priming abilities in tumor-bearing conditions. Here, we also comment on IL-33 data in human cancers and explore the idea that endogenous IL-33 may not deserve its reputation for promoting tumor growth. In fact, tumors may hijack the IL-33/ST2 axis to avoid immune surveillance and escape antitumor immunity.

Possible Role of Interleukin-31/33 Axis in Imatinib Mesylate-Associated Skin Toxicity

Imatinib mesylate is a small-molecule tyrosine kinase inhibitor (TKi) designed to target c-ABL and BCR-ABL, approved for the treatment of chronic myeloid leukemia and gastrointestinal stromal tumors. Adverse cutaneous reactions induced by imatinib are frequent, generally moderate, and dose-dependent. The aim of this work was to investigate the possible contribution of interleukin (IL)-33 and IL-31, cytokines involved in disorders associated with itching, in the pathogenesis of pruritus in a patient undergoing imatinib mesylate treatment. His IL-31 and IL-33 serum levels were significantly higher than in the control group (respectively 96.6 pg/mL vs. 7.623±7.681 pg/mL and 27.566 pg/mL vs. 6.170±7.060 pg/mL). In light of these findings, imatinib mesylate-related symptoms of dermatologic toxicities might be related to the release of IL-31 and IL-33. In particular, it is supposable that TKi usage could cause keratinocyte injury, the release of IL-33, and the consequent interaction with its receptor on mast cells that induces the secretion of several factors capable of causing skin manifestations, including IL-31, a known pruritus-inducing cytokine. This report, to the best of our knowledge, is the first work describing the possible involvement of the IL-31/IL-33 axis in the pathogenesis of skin side effects related to imatinib mesylate treatment.

Discovery of a Metastatic Immune Escape Mechanism Initiated by the Loss of Expression of the Tumour Biomarker Interleukin-33

A new paradigm for understanding immune-surveillance and immune escape in cancer is described here. Metastatic carcinomas express reduced levels of IL-33 and diminished levels of antigen processing machinery (APM), compared to syngeneic primary tumours. Complementation of IL-33 expression in metastatic tumours upregulates APM expression and functionality of major histocompatibility complex (MHC)-molecules, resulting in reduced tumour growth rates and a lower frequency of circulating tumour cells. Parallel studies in humans demonstrate that low tumour expression of IL-33 is an immune biomarker associated with recurrent prostate and kidney renal clear cell carcinomas. Thus, IL-33 has a significant role in cancer immune-surveillance against primary tumours, which is lost during the metastatic transition that actuates immune escape in cancer.